The morphometrical and immunohistochemical investigation of the effect of topiramate on liver and the role of neuropeptide Y receptor in an obese female rat.

OBJECTIVE: We aimed to investigate the possible effect of topiramate (TOP, 0.02 mg/kg/day) on the livers in a high-fat diet (HFD)-induced obesity rat model. The other objective was to evaluate the relationship between TOP administration and NPY level using anti-NPY1R antibody. METHODS: Twenty-four adult female Wistar albino rats were randomly assigned into four equal groups as follow: control (CONT), obese (OBS), TOP, and OBS+TOP. All liver samples were investigated using the stereological analysis, as well as immunohistochemical and histopathological examination. RESULTS: The total number of hepatocytes was significantly decreased in the OBS+TOP group compared to the CONT group or the OBS group (p < 0.05). We found a significant increase in the mean volume of liver in the OBS group compared to the CONT group (p < 0.05). Also, the mean volume of liver was significantly decreased in the OBS+TOP group compared to the OBS group (p < 0.05). CONCLUSION: Taken together, our findings suggest that decreased liver volume is possibly attributed to TOP administration via setting the NPY level in the obese rats. Further, the side effects of TOP in combination with health risk of obesity may have led to an increase in hepatotoxicity and the subsequent hepatocyte loss (Fig. 7, Ref. 56). Text in PDF www.elis.sk Keywords: immunohistochemistry, liver, neuropeptide Y, obesity, rat, topiramate.

A stereological study of the effects of antidepressants on postmenopausal rat kidney.

Many factors can cause depression including genes (DNA), brain chemistry or stress. Antidepressant drugs affect the brain, heart, liver and kidney. We investigated the effects of the antidepressant drugs, amitriptyline (AMI) and paroxetine (PARO) on kidney. We used 24 adult female rats that were ovariectomized bilaterally 7 days before the experiment. The ovariectomized (OVX) animals and healthy control rats were divided into four equal groups for 4 weeks: control group, OVX control group (sham), AMI group and PARO group. Following the experimental period, the Cavalieri method was applied to sections of the kidney. PARO produced adverse effects on distal and proximal tubule volume, but AMI had no effect on the volume of distal and proximal tubules. Both PARO and AMI decreased the volume of Bowman spaces. PARO also damaged the kidney tubules and cells.

The role of HMGB1 in liver inflammation in obese rats.

Obesity is a chronic disease that is characterized by increased body fat owing to imbalance between consumed and expended energy. Inflammation generally is accompanied by accumulation of excess lipid in adipose tissue and liver. High mobility group box-1 (HMGB1) participates in the pathogenesis of inflammatory diseases. We investigated the relation of the number of HMGB1 positive cells to body mass index (BMI), liver inflammation and the number of Kupffer cells. We divided 18 female Wistar albino rats into two groups: group 1, untreated control fed normal commercial rat diet and group 2, obese rats fed a special diet containing 40% fat. The plasma concentrations of cholesterol, glucose, superoxide dismutase enzyme (SOD) and catalase activities were measured for all animals. The numbers of hepatocytes, Kupffer cells and HMGB1 positive cells were counted using stereological methods. The mean numbers of Kupffer cells and HMGB1 positive cells were higher for group 2 than for group 1. The concentrations of plasma cholesterol and glucose levels also were higher in group 2. Plasma levels of SOD and catalase were significantly lower in group 2 compared to group 1. The number of HMGB1 cells was related directly to BMI and inflammation. The role of HMGB1 was demonstrated for the liver of the obese group. We demonstrated the relations among HMGB1, BMI, obesity and inflammation.

Protective effects of luteolin on rat testis following exposure to 900 MHz electromagnetic field.

Increasing cell phone use calls for clarification of the consequences of long term exposure to electromagnetic fields (EMF). We investigated the effects of EMF on the testes of 12-week-old rats as well as possible protective effects of luteolin on testis tissue. Twenty-four Wistar albino rats were randomly divided into four groups: control, EMF, luteolin, and EMF + luteolin. The number of Leydig cells, primary spermatocytes and spermatids were reduced in the EMF group compared to the control group. In the EMF + luteolin group, the number of Leydig cells, primary spermatocytes and spermatids was significantly greater than the EMF group. We found an increase in superoxide dismutase (SOD) activity in the EMF group compared to the control group. In the EMF group, we found decreased wet weight of testes and serum testosterone levels compared to the control group. Decreased SOD enzyme activity, and increased serum testosterone levels and weight of the testes were observed in the EMF + luteolin group compared to the EMF group. EMF also affected sperm morphology. We found that in rat testis repeated exposure to 900 MHz EMF caused changes in testicular tissue and that the antioxidant, luteolin, substantially reduced the deleterious effects of EMF.

Histomorphometric changes in the placenta and umbilical cord during complications of pregnancy.

Pregnancy complications may cause morphological changes and circulation defects in the placenta, which may lead to morbidity and mortality in fetuses and newborns. We investigated structural changes in the placenta and umbilical cord under various abnormal maternal conditions. Placenta and umbilical cord specimens were obtained from pregnant women during labor at 37 - 42 weeks gestation. Volumetric measurements were made for each placenta and umbilical cord using the Cavalieri method. Significant differences were observed for volumetric densities of total villi, syncytial knots, intervillous vessels and perivillous fibrin deposition. We observed particular increases in the volumetric parameters of the pre-eclampsia group compared to the other groups. The tunica media of the umbilical arteries was increased significantly with intrahepatic cholestasis.

A histopathological and stereological study of liver damage in female rats caused by mercury vapor.

We examined the possible effects of elemental mercury vapor on the liver of the female rats. We divided the animals into an untreated control group and an experimental group that was exposed to mercury vapor for 45 days. Liver samples were obtained for histological and stereological analysis. The total liver, parenchyma and sinusoid volumes were increased significantly in the mercury vapor treated group compared to controls. Also, the mean density, total number and mean nuclear diameter of hepatocytes, except for binucleated hepatocytes, was decreased in the experimental group compared to controls. Light and electron microscopy revealed alterations of liver structure of the experimental animals compared to controls.

Effects of prenatal diclofenac sodium exposure on newborn testis: a histomorphometric study.

Diclofenac sodium (DS) is used primarily to treat fever and to alleviate pain and inflammation. We investigated the effects of DS exposure during gestation on the testes of rat pups to investigate the safety of its use during the prenatal period. Pregnant rats were separated into control, saline, low dose, medium dose and high dose groups. DS was given between weeks 15 and 21 of gestation. Total numbers of spermatogonia and Sertoli cells were counted in the testes of 7-day-old male rats using the physical disector method. By the end of the study, the total number of Sertoli cells was decreased significantly in a dose dependent manner in the medium and high dose groups compared to controls. No significant differences were found in the total number of spermatogonia in the control, saline and low dose DS groups. Medium and high dose DS administration reduced the total number of spermatogonia compared to other groups. We suggest that prenatal administration of DS can cause deleterious effects on the testis development, especially in high doses.

A stereological and histopathological study of the effects of exposure of male rat testes to mercury vapor.

Mercury is ubiquitous in the environment; it is an occupational pollutant and a potential toxicant. We investigated the effects of exposure of rat testes to mercury vapor (Hg(0)). Twelve male rats were divided into two groups of six: the rats of the Hg(0) group were exposed to mercury (1 mg/m(3)/day) in a chamber for six weeks; the control group rats were housed under the same conditions without exposure to Hg(0). After the experimental period, the testes were removed, sections of testis were evaluated histopathologically after hematoxylin and eosin staining, and stereologically using the Cavalieri principle and optical fractionator methods. We found significant decreases in the total volume of testis, diameters of seminiferous tubules and total volume of seminiferous tubules. Significant decreases were detected in the numbers of Sertoli cells, spermatogonia, spermatocytes and spermatids of the Hg(0) group compared to the control group. In the Hg(0) exposed group, spermatogenic cells were degenerated and seminiferous tubules were atrophied.

Efficacy of Ankaferd Blood Stopper on bone healing in diabetic rats: a stereological and histopathological study.

We evaluated the effects of Ankaferd Blood Stopper (ABS) and routine antibiotic prophylaxis (AP) on early healing of bone defects in diabetic rats. We used 48 rats in the study. Diabetes was induced in 24 rats using streptozotocin; the remaining 24 healthy untreated rats served as controls. Twelve of the diabetic rats and 12 of the healthy rats were treated with AP for 3 days before surgery. Bilateral bone defects were created in the mandible of all animals. ABS was applied to the defects on the left sides of the mandibles, while nothing was applied to the right sides. Animals were sacrificed on days 7 and 14 after operation and examined for histopathology and by stereology. The volume of newly formed bone was significantly less in the diabetic rats on both days 7 and 14. Local administration of ABS significantly increased the mean volume of newly formed bone in both diabetic and nondiabetic rats at days 7 and 14. No significant difference in new bone formation was found between AP and ABS treatment in diabetic rats. Both AP and local administration of ABS have beneficial effects on bone healing in diabetic animals.

Effects of high fat diet induced obesity on peripheral nerve regeneration and levels of GAP 43 and TGF-ß in rats.

The increasing frequency of obesity is important because of its accompanying related health problems. The effects of obesity on peripheral nerves have not been elucidated. We investigated the effects of obesity on sciatic nerve regeneration using electrophysiology, stereology, immunohistochemistry, histopathology and functional tests. We used control, obese, control injured and obese injured groups of rats. Electrophysiological results showed that nerve conduction velocity and EMG were same in the experimental groups, but the amplitude of the compound action potential of the control group was significantly higher than that of the obese group. Examination of the nerves showed that the control and obese groups had both larger axon diameters and thicker myelin sheaths. The number of myelinated axons was decreased in both of the injured groups. Axon diameters and myelin sheath thicknesses of the control injured group were significantly greater those of the obese injured group. There were no significant differences in functional tests among the groups. Although growth associated protein 43 immunostaining in the control injured group was significantly greater than that of the obese injured group, no significant difference was observed between the control and obese groups. There was no significant difference in immunohistochemical staining for transforming growth factor beta 3 between the control injured and obese injured groups. Our results suggest that obesity may affect peripheral nerve regeneration negatively after crush injury.

Effects of prenatal exposure to diclofenac sodium and saline on the optic nerve of 4- and 20-week-old male rats: a stereological and histological study.

We investigated the effects of diclofenac sodium (DS) on development of the optic nerve in utero. Pregnant female rats were separated into three groups: control, saline treated and DS treated. Offspring of these animals were divided into 4-week-old and 20-week-old groups. At the end of the 4th and 20th weeks of postnatal life, the animals were sacrificed, and right optic nerves were excised and sectioned for ultrastructural and stereological analyses. We demonstrated that both DS and saline produced structural and morphometric changes in the total axon number and density of axons, but decreased the myelin sheath thickness in male optic nerves. All ultrastructural and morphometric features were well developed in 20-week-old rats. We showed that development of the optic nerve continues during the early postnatal period and that some compensation for exposure to deleterious agents in utero may occur during early postnatal life.

Stereological and histopathological evaluation of ovary and uterine horns of female rats prenatally exposed to diclofenac sodium.

In this study, we investigated the morphometric and histological alterations of the ovary and uterine horns in 4-week-old rats that were prenatally exposed to diclofenac sodium (DS). For this purpose, pregnant rats were divided into two groups: the control and drug-treated groups. Beginning from the 5th day after mating through the 15th day of pregnancy, DS (1 mg/kg daily) was intraperitoneally injected in the treated group. No injection was given to the rats in the control group. After spontaneous delivery, male offspring were obtained. At the end of the 4th week, ovary and uterine horn samples were removed. Following dissection and routine histological preparation, histopathological and stereological investigations were carried out. Our results indicate that DS application leads to a decrease in the mean volume fraction of the uterine horn. Moreover, there was an increased volume fraction in some structures of the ovary; like the cortex, medulla and zona granulosa. There was no difference found between the two groups in terms of the mean volume of the antrum and the Graafian follicle fraction. Finally, in light of our findings, we may suggest that DS may lead to adverse effects in rats that are prenatally subjected to this drug.

Effects of diabetes and ovariectomy on rat hippocampus (a biochemical and stereological study).

Oxidative stress is one of the main reasons of both menopause and diabetes. So, it plays crucial role in the pathogeneses of that condition and disease. Therefore, the objective of the present study was to investigate the effects of menopause and diabetes upon the hippocampus using a rat model. Adult female Sprague Dawley rats (n = 24) were allocated randomly as follows; control (C group) ovariectomized (O group), diabetic (D group) and ovariectomy plus diabetic groups (DO group) (n = 6; in each group), respectively. For evaluating the results, tissue biochemistry and stereological analysis were made. Biochemistry results (lipid peroxidase (LPO); catalase (CAT); superoxide dismutase (SOD); total glutatyon (GSH); and myeloperoxidase (MPO) values) in Group C-DO were determined as 12.27, 21.88, 23.08 and 29.90 nmol/gr tissue; 59.3, 70.06, 69.7 and 78.1 mmol/min/mg tissue; 174.2, 156.4, 159.7 and 154.6 mmol/min/mg tissue; 3.63, 3.61, 4.21 and 3.97 nmol/mg tissue; and 5.05, 5.68, 5.58 and 6.19 µmol/min/mg tissue, respectively. Moreover, both menopause and diabetes led to change of lipid profiles. There were significant differences between the control and other groups (Group C and D-DO) (p < 0.01) and among experimental groups (p < 0.01) in terms of neuron number. When the volumes of the hippocampus were compared, there were no significant differences between the all groups (P > 0.05). At this point, we suggested that diabetes could aggravate deleterious effects of ovariectomy.

Stereological and histological analysis of the developing rat heart.

We studied with quantitative and microscopical methods the heart of rats divided into five age groups: embryos at the age of 11 days, fetuses at the age of 16 days and 20 days and also heart samples of 3-day-old pups and young adults (5 weeks of age) were used (n = 10 samples in each group). At the end of the study; heart samples were obtained from all animals. Stereological estimations were performed on heart volume, volume of heart lumen (ventricles and atria), volume of myocardium, numerical density of the myocyte nuclei and mean nuclear diameter of myocytes. Volumetric values and numerical data were estimated via Cavalieri method and physical dissector, respectively. In this study, histological examination was performed at light and electron microscopic levels. The numerical density of the myocyte nuclei increased from fetuses to young adults. Differences between embryos and fetuses, between fetuses and 3-day-old pups, and between 3-day-old pups and young adults were statistically significant. These results indicate that myogenesis continued in the rat myocardium during prenatal life and after birth.